Hybrid active filter control for harmonic reduction in quadratic boost converter-integrated grid systems

Abstract

This article examines the proportional-integral (PI) and fractional-order proportional-integral-derivative (FOPID) controllers for a quasi-buck converter-hybrid active filter (QBC-HAF) to improve the harmonic suppression and power quality of a hybrid energy storage system (HESS) fed to the grid. This system uses a high-gain QBC, which is connected to a VSI to control the DC-link voltage and to allow controlled energy transfer from photovoltaic and battery sources. A MATLAB/Simulink test bed and hardware prototype were developed to validate performance. The results demonstrate the enhanced stability and quality of the output waveforms for both controllers, with the FOPID providing better harmonic suppression, reducing output current total harmonic distortion (THD) from 4.34% to 4.14% and output voltage THD from 4.75% to 4.42%. The simulation results were validated using experimental tests, showing that the FOPID-controlled QBC-HAF system is suitable for power quality improvement, voltage stabilization, and dynamic performance in renewable integrated grids.